The invention relates to methods and devices for scanning an oral environment. More specifically, the invention relates to a computer-based system for scanning and analyzing images of the mouth for storage and comparison to known images and prior images of the same patient.
There has been as shift in recent years in dentistry from a philosophy of drilling and filling teeth to one of prevention and cosmetics. Many serious dental health problems can be treated or prevented if detected early. Such detection relates to the appearance and color of the teeth and gums. Due to concerns about the visual appearance of their teeth, many people also undergo clinical procedures to enhance their smiles or to correct certain defects. Such clinical or cosmetic procedures of this type generally involve the modification of tooth shape, alignment, and color.
The appearance, i.e., color and texture, of the gums provides an indication about a patient""s dental health. If the gums are red or swollen, this may indicate the onset of gingivitis or other gum disease. Dental professionals (e.g., dentists, hygienists) presently xe2x80x9ceyeballxe2x80x9d the teeth and gums to determine whether or not there are any health issues. The dental professional may record on the patient""s chart that the gums appear xe2x80x9cpinkxe2x80x9d or xe2x80x9cred.xe2x80x9dAt the patient""s next visit, the dental professional may notice that the gums still appear red, or that they appear more red or pink. It is difficult, however, to determine whether the color or visible texture of the gums has changed, e.g., are the gums more or less red than the previous visit, or are they different in some other way. The dental professional may have seen numerous patients since a particular patient""s last examination and may not remember the precise color of the gums of the particular patient. This is made further difficult because the gum color is usually a shade of pink or red and descriptions are subjective.
As a person ages or as disease progresses, the gum tissue will often recede from the teeth. This condition may result in bone loss. The level of the gum-line can also indicate whether the gums, the tooth, or even the underlying bones are healthy, especially when compared to the previous level of the gum-line to determine whether it has receded. The dental professional may attempt to measure the level of the gum lines with a measuring device placed along the tooth structure. Gingival height is typically measured from the incisal edge of the tooth to the gum tissue. This technique is very imprecise for measuring as different dental professionals may measure slightly differently, and the same dental professional may even measure slightly differently on different days from different spots. This makes comparison to a standard or to the patient""s previous measurement inaccurate or difficult at best.
There is also a trend in dentistry in that many patients desire cosmetic treatments to modify tooth alignment, size, and color. It may be necessary to reduce the tooth size or to increase the size with porcelain laminate veneer. The existing protocol for these procedures requires the dental professional to take an impression of the patient""s teeth and construct a replica of the teeth from the impression. The dental professional then measures the replica using a ruler or similar device to get the size of the teeth and their position and relationship to each other. The dental professional must then perform calculations to determine the proper treatment. While certainly better than an xe2x80x9ceyeballingxe2x80x9d technique, this procedure still lacks precision. Each dental professional may measure the teeth in a slightly different way, so that the data are not reproducible when the patient visits different dental professionals. Other sources of potential error include faulty or out-dated equipment.
Patients may also desire to change the shade of their teeth, generally by whitening or otherwise brightening them. A necessary first step in this regard is to determine the shade of the existing teeth. The goal may be to whiten all of the teeth to a certain predetermined shade, or it may be to match the shades of some of the teeth to the others. Currently, the dental professional will utilize a standardized shade guide, such as VITA(trademark), BIOFORM(trademark), and CHROMASCOP(trademark). These guides are generally used in a rudimentary fashion. The guide itself is a plastic plate with color tabs that are shaped like teeth. The dental professional holds one or more of the tabs up to the patient""s tooth and visually determines the closest match. There is a great deal of subjectivity involved in such a measurement and the dental professional may not be sufficiently skilled or qualified for the task. The lighting and ambient light in the room can also affect selection of the tooth shade.
The current method of recording these data is that the dental professional typically writes his findings on the patient""s chart. Not only does this method present the problems of subjectivity of the measurement and difficulty in comparing one visit with the next, the lack of precision of language can present challenges for the dentists and their assistants. This is especially true if a patient sees a different dentist or a different hygienist is reading the chart for a subsequent examination. This is not a problem with certain measurements, such as x-rays, that are kept in the patient""s file and can be read by any dental professional without the need for remembering and interpreting prior subjective measurements and imprecise language.
U.S. Pat. Nos. 5,766,006, 5,961,324, 6,132,210, 6,206,691, and 6,210,159 disclose systems and methods for determining tooth shades by comparing those shades to standard shades. This information can be used to more accurately determine a patient""s tooth shade and correlate this to the standard for changing the shade of the tooth. The systems and methods of these patents are generally intended for use in connection with the restoration of a single tooth, rather than for monitoring the patient""s entire mouth.
Thus, there is a need for a system for obtaining dental information from a patient wherein reliable, reproducible information is obtained regarding the color and orientation of the patient""s teeth, as well as the color and position of the patient""s gums with respect to the teeth, and for saving the data in a format from which they may be readily retrieved and used in the future. There is also a need to use these data for comparison to standardized guides for tooth and gum health, as well as for tooth size, shape, shade, and other information. The present invention provides these and other features in a manner which is not heretofore known in the art.
The invention relates to an apparatus for scanning an oral environment including a mouthpiece, a scanning device disposed within the mouthpiece for capturing one or more images of the oral environment, and an electronic storage device for storing each image of the oral environment. The storage device is connected to the scanning device, which will preferably include a camera capable of moving within the mouthpiece.
The device may further include one or more mirrors slidably or rotatably attached to the mouthpiece to redirect images at various angles into the scanning device. The electronic storage device preferably includes a CD, a DVD, digital tape, a computer hard drive, a flash card, a smart card, or an electronic diskette. In another embodiment, the electronic storage captures each image for storage on photographic paper or negative. For this embodiment, the storage device comprises a computer and associated printer. The mouthpiece includes a tab for a patient having teeth to bite on to temporarily hold the apparatus adjacent the patient""s teeth. A track is typically included in the mouthpiece on which the scanning device moves. The apparatus may also include a monitor to display the captured image.
The invention also relates to a method of obtaining and manipulating an electronic image of a plurality of a patient""s teeth including scanning the plurality of teeth to provide a first electronic image that includes at least one dental characteristic of gingival color, gingival height, tooth color, tooth height, or tooth width of each tooth of the plurality of teeth, and transferring the first electronic image to an electronic storage device. The method may further include scanning the plurality of teeth to provide a second electronic image that includes at least one dental characteristic of gingival color, gingival height, tooth color, tooth height, and tooth width of each tooth of the plurality of teeth and comparing the at least one dental characteristic of the second electronic image to that at least one dental characteristic of the first electronic image. The method may further include comparing the dental characteristic of the teeth of the first electronic image with the same dental characteristic in a dental standard image. Preferably, these comparisons are performed electronically. The method may also include calculating the ratios of the widths of at least two of the plurality of teeth in the first electronic image with respect to each other. The method may also include matching the tooth color of at least one tooth of the first electronic image to the color of an adjacent or contra-lateral tooth to facilitate restoration of the at least one tooth.
In anther embodiment, the method also includes scanning a preparation to determine the color of the preparation and provide a second electronic image and matching the color of the preparation in the second electronic image to the tooth color of the first electronic image. Preferably, the scanning is performed by a camera and the electronic storage device includes a CD, a DVD, digital tape, a computer hard drive, a flash card, a smart card, or an electronic diskette. Preferably, the image may be displayed on a monitor and the displaying is concurrent with the transferring to the electronic storage device.